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A249853 Numbers whose cubes become squares if one of their digits is deleted.

%I A249853 #28 Oct 27 2023 22:15:20
%S A249853 4,5,6,10,20,21,25,40,44,64,90,100,129,160,200,250,360,400,490,500,
%T A249853 600,640,810,1000,1210,1440,1690,1960,2000,2025,2100,2250,2500,2560,
%U A249853 2890,3240,3610,4000,4400,4410,4840,5025,5290,5760,6250,6400,6760,7290,7840,8410
%N A249853 Numbers whose cubes become squares if one of their digits is deleted.
%C A249853 A245096 gives the numbers whose squares become cubes if one of their digit is deleted.
%C A249853 Numbers with single-digit cubes are not included. - _Davin Park_, Dec 30 2016
%H A249853 Alois P. Heinz, <a href="/A249853/b249853.txt">Table of n, a(n) for n = 1..1000</a> (first 100 terms from Paolo P. Lava)
%e A249853 21^3 = 9261 and sqrt(961) = 31.
%e A249853 44^3 = 85184 and sqrt(5184) = 72.
%e A249853 45625^3 = 94974853515625 and sqrt(9474853515625) = 3078125.
%p A249853 with(numtheory): P:=proc(q) local a,k,n;
%p A249853 for n from 1 to q do a:=n^3; for k from 1 to ilog10(a) do
%p A249853 if type(sqrt(trunc(a/10^(k+1))*10^k+(a mod 10^k)),integer)
%p A249853 then print(n); break; fi; od; od; end: P(10^9);
%t A249853 f[n_] := !MissingQ@SelectFirst[Delete[IntegerDigits[n^3], #] & /@ Range[IntegerLength[n^3]], IntegerQ@Sqrt@FromDigits@# &];
%t A249853 Select[Range[4, 1000], f] (* _Davin Park_, Dec 30 2016 *)
%Y A249853 Cf. A249587, A225885.
%K A249853 nonn,base
%O A249853 1,1
%A A249853 _Paolo P. Lava_, Nov 07 2014